I made a 9-key Programmable Mechanical Keyboard

[edwardrford]

Hey All - this is my first post - though I've been lurking here for some time.

The idea of doing a from scratch keyboard has crept into my mind and I haven't been able to get rid of it. I'd like to do the whole thing (minus the firmware) - Design and mill the PCB, cover plate, and case. It's a big task and I haven't convinced myself to start just yet.

instead, i decided to test the waters by making a 9-key programmable keypad. I used MX Blue switches and some spare keycaps I had around the shop.

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I used a promicro for the controller, but because it is only 9 keys I just directly mapped each key to a pin instead of doing a matrix. Right now the 'firmware' is just an arduino sketch which looks for the button press, then sends out the appropriate ASCII code.

pcb.JPG (134.86 KiB) Viewed 1464 times

The PCB design was pretty straight forward - I wanted to keep everything in a small footprint, but I also wanted it to be a single sided board so I could cut it on my CNC without worrying about locating for a flip, and keeping everything lined up. All in the board was 2.75" x 3.125" and I managed to get all the traces on one side without growing it too much.

IMG_2674.JPG (145.43 KiB) Viewed 1464 times

I used my CNC to cut the cover from mahagony and the bezel from a piece of 9mm baltic birch. everything snap fit nicely together. Although, I may switch out baltic birch bezel for a piece of aluminum to give the whole thing some weight.

Anyway - thanks for looking, let me know what you think!

-Edward

[OldIsNew]

That's very cool! Very nice looking case and I love the PCB. I'm unfamiliar with actually making a DIY PCB - what did you use to lay down the traces?

[edwardrford]

Thanks!

I used a program called Eagle - it's pretty popular in the PCB world, was bought by autodesk about a year ago. There is a free version that lets you make boards up to 4"x6" (single or double sided) - beyond that you have to pay the subscription.

The software is not the most intuitive thing in the world (think mid 80's autocad style UI) but it works and has a lot of libraries baked in, so selecting components (like the arduino and the mx switches in my case) is no more than point and click and place.

-Edward